Sightsavers has embarked on a 10-year program to eliminate onchocerciasis, also known as river blindness, a leading cause of preventable blindness that is transmitted by the bite of the black simulium fly. Its first stop is in the Democratic Republic of the Congo, where the disease is endemic, but it plans to invest more than £27 million (€32.5m-$42.0m) throughout Africa, including the Ivory Coast and Angola, in the next decade. Merck & Company has donated the treating dug, Mectizan, since 1987, and Sightsavers will work to get the treatment to remote communities using local volunteers. Its goal is to increase annual treatments by 30 percent.